Science and technology reporter, BBC News
Most people know that you should not throw away letters or bills that contain your personal information.
The government estimates that ID fraud cost £1.7 billion in 2005
If you do, an unscrupulous criminal might raid your bin in the middle of the night and steal your discarded details.
By the time you sit down to breakfast, the midnight marauder will have assumed your identity and started applying for mortgages and credit cards in your name.
In reality the process takes a lot longer but this kind scenario has had an impact on the public consciousness.
People are now aware of ID fraud and some are starting to take measures to prevent it.
However, the problem has not gone away.
The government has estimated that ID fraud cost the UK £1.7bn last year and according to CIFAS, the UK's fraud prevention service, identity theft has risen more than six-fold from 20,000 cases in 1999 to 137,000 in 2005.
Part of the reason for this dramatic surge is that with our growing addiction to broadband, personal data can increasingly be found online.
In 1996 there were no electronic public records in the UK. Today there are nearly 700 million.
Couple that with the fact that ID fraud is such a profitable enterprise, it is no wonder that ID thieves have turned to the web for their data raids.
"Criminals are always looking for new ways to make money, online identity theft and fraud are the latest techniques," said Detective Chief Superintendent Nigel Mawer at the Metropolitan Police Economic and Specialist Crime Unit.
Security companies have become aware of this and have started to offer products that could help people protect themselves.
One is Garlik, set up by the founders of the internet bank Egg, along with privacy experts, lawyers, and researchers from the University of Southampton.
The aim of the company is to give people power over their digital identities by showing them what information is out there on the web, how it can be exploited and what steps they might take to reduce the risk of becoming a victim of digital identity fraud.
A scan of my digital footprint by Garlik found 1,595 references from 913 different sources, detailing everything from my home address and girlfriend's name to maps of my house and details about my parents.
Other details including my credit rating and estimated salary were also present.
According to Garlik, all of the information was found on websites and in publicly accessible databases. There was more than enough information for an unscrupulous criminal to start taking over my identity.
Although, as a BBC web journalist my online profile maybe atypical, Garlik estimates that the average Briton's personal details can be found in over 1,000 places on the web.
"Individuals have an asset called their identity," said Dr Tom Ilube, CEO of Garlik. "It is valuable to you and valuable to those people that want to abuse it. People need to be careful."
The company builds a subscriber's profile using semantic web applications, developed at the University of Southampton for the next generation of the web, to scour more than four billion web pages for personal data.
The Garlik technology is the largest commercial application of semantic tools, designed to bring meaning to large amounts of data, so far.
TEN POINT GUIDE TO PROTECTING YOUR IDENTITY ONLINE
Operate on the internet in the same way as you do offline
Question why a Web site is asking for information
Never give online security details unless completely necessary
Look after your password
Never click on links in emails
Keep security software up-to-date
Keep your internet connection secure using encryption
If it seems too good to be true, it probably is
Source: Security Report Online Identity Theft
The personal information found across the web is presented as a monthly statement, showing a user what has been found, what has changed and what presents a potential problem.
For example, if your name, address, mobile phone number or mother's maiden name appeared on an unknown website based in Eastern Europe, the system would flag that up as a possible concern.
Advice on how to reduce the risk and impact of identity theft is also part of the service.
The company's system also analyses public records such as the Land registry, credit files and the Register of Births, Deaths and
Marriages to build a complete picture of a subscriber's online digital footprint.
In addition, the "intelligent" system can analyse the content of web pages to build up a picture of your relationship to other people mentioned in the pages or databases.
So if your name appears alongside someone else's regularly, then it will assume you have a relationship with them and will flag this up to you.
Changes to these relationships can be used as an early warning signal for ID fraud.
"If someone is pretending to be you (i.e. they have stolen your identity) then it can show up as a list of people that you do not know," said Dr Ilube.
DataPatrol, as the Garlik service is known, is currently free but will change to a subscription rate in the New Year.
It is one approach that could help protect your identity online.
But Detective Chief Superintendent Mawer also urged people using the web to follow the 10-point guide developed by groups such as the Metropolitan Police, Lloyds TSB and Yahoo.
The plan is outlined in a security report published earlier this year.
Suggestions include never giving any online security details to anyone unless it is completely necessary and asking yourself why a website is asking for personal information.
"By protecting themselves against the growing threat, users are also protecting others," he said.